The present invention is directed to an input method for programming axial movements and events for industrial controllers.
It is known that graphical input devices and a display screen can be used for graphically visualizing elements of a control procedure of an industrial process system and for controlling the movements of a processing machine. For example, see Hans D. Kief: xe2x80x9cNC/CNC Handbuchxe2x80x9d [NC/CNC Handbook] 1995/96, Hanser Verlag, page 297, Figure 1 and page 318, Figure 3. Thus, for example, a user may graphically input and vizualize geometric and/or technical information. These graphics, which, for example, visualize the geometry of a workpiece; are used directly for programming the controller.
In the case of traditional machine tools, programming issues have less to do with machining a workpiece than with the interaction of two or more axes for the implementation of a desired production process. Different functions of the production process can be handled by the controller. Control of different functions is thereby enabled including, positioning, synchronization, and cam behavior, as well as the integration of time and path conditions and events and combinations thereof.
Input methods today depend primarily on the electrical or electronics engineer who converts given engineering problems into a programming language that can be understood by the controller. The conceptual viewpoints of a mechanical engineer, i.e., a machine designer, however, is poorly supported by traditional programming solutions. Therefore, an object of the present invention is to make available an input method that supports the approach of the mechanical engineer and thus greatly simplifies data input for the user.
According to the present invention, this object is achieved for a method comprising the following steps:
a) editable blank diagrams for path-time curves for one axis at a time and/or pathxe2x80x94path relationships for pairs of leading axes and following axes are visualized for the user;
b) the path and time limits and/or path and time units are defined as needed;
c) the path-time curves and/or the pathxe2x80x94path relationships are entered into the diagrams using the input devices;
d) the control program and/or the control code for the production process are subsequently generated by the controller;
where edited changes in the control program or in the control code are both active and retroactive.
An important advantage of the claimed input method for programming axial movements and events in industrial control systems is that it supports the thought processes of a mechanical engineer, who is thinking about abstract axial movements and movement processes. Using the claimed method, especially with regard to programming movement controls, a user can easily enter the path-time curve of axial movements into path-time diagrams. With the help of manual input devices, the user can easily enter the relationships between leading axes and following axes in pathxe2x80x94path diagrams. The inputs are then visualized within previously defined path and/or time limits. The user is thus able to concentrate on path and time intervals, and therefore can focus on small sections when programming complex movement processes. In addition, the user can select the best path and/or time units when labeling the abscissa and ordinate of each blank diagram.
The user can visualize the movements of different axes of the same machine in separate diagrams. This ability facilitates the programming process because the user can process the movement sequences of one axis and the relationships of the leading axis and the following axis separately and in succession.
Another advantage of the present invention is that different types of axial movement such as axial positioning, synchronous operation or curve synchronization can be represented in the same type of diagram.
Another advantage of the present invention is that, after inputting path-time curves of the respective axes and/or inputting pathxe2x80x94path relationships for pairs of leading and following axes, a corresponding control language and control program and/or control code for the controller can be generated automatically from the diagrams. Generation of code in a programming language that can be understood by the controller is therefore part of the system output. The control language may be in the form of a higher programming language or it may be in a graphic form (e.g., a flowchart).
Another advantage of the present invention is that the user is supported in traditional forward engineering by a completely integrated toolkit:
the above-mentioned input method;
controller language; and
controller code.
In addition, any revisions made by the user in a later phase are automatically incorporated into earlier entries. In this way, the user is supported in round-trip engineering, i.e., changes made by an electrical engineer at the programming level (at the level of the controller language) are included in a diagram for the mechanical engineer (said input method). Thus, consistency in both directions is ensured at all levels.
In an embodiment of the present invention, axial positioning sections and/or axial synchronous sections may be entered for path-time curve diagrams. Thus, the user has the option of having the chronological sequence of positioning and synchronous curves presented in one diagram, i.e., to see everything visualized at once. Another advantage of this joint representation is that the respective derivatives (speed, acceleration and rate of change) can be calculated and visualized on the basis of this diagram.
In another embodiment of the present invention, symbols representing events and control instructions for the path-time curves and/or the pathxe2x80x94path relationships, are entered into the diagrams with the help of an input device. Therefore, an axial movement can be represented as a response to an external event, and furthermore, a complex and/or dependent axial process can be modeled by the introduction of control instructions or logical conditions.
In another embodiment of the present invention, control information contained in an event or control symbol, can be visualized via an input device in a partial image or a subfigure correlated with a diagram. Thus, additional detailed information relevant in the current stage of work is available to a user in a simple and ergonomic manner.
In another embodiment of the present invention, first, second, and/or third derivatives of a path-time curve, may be visualized on a display screen at the control end. Verification of the dynamic response of the controlled axis can be monitored through this representation of the speed, acceleration and rate-of-change diagrams. In other words, the system knows the physical limits of each axis and simply does not allow movement processes that would extend outside these physical limits.
In another embodiment of the present invention, a derivative may be determined and visualized via an action from the input device, and any effect of that derivative on another derivative or on an output path-time curve for the controller may also be visualized. Thus, the user has the option of further optimizing the derivatives generated by this system according to the movement function via an interactive process utilizing an input device. The effects of a modification entered by a user on another derivative and on the output path-time curve and on an axis are promptly visualized on the control end after the input is complete. In this way, the user can visually and immediately evaluate the effects of any changes made.
In another embodiment of the present invention, some or all of the path-time curves can be visualized in a time-synchronous manner in a subfigure or partial figure, and can be correlated by using an input device. Thus, the user has the option of evaluating the path-time curves of all axes, or a subset thereof, in an overall diagram with a time-synchronous display. The user can thus clearly see where the axes are located in the system at any given time. Then, with the help of the input device, the user can easily specify a synchronous start of movements of multiple axes. The user thus has the option of introducing further optimization of the movement.
In another embodiment of the present invention, some or all of the pathxe2x80x94path relationships can be vizualized. The user can thus view all the pathxe2x80x94path relationships of the leading axis and the following axis which are present in the system or a subset thereof in an overview diagram.
In another advantageous embodiment of the present invention, a context-specific toolbar may be provided for the user, with various symbol elements available for entering path-time curves and/or pathxe2x80x94path relationships. Using a keyboard, mouse, light pen or other input device, the user can operate the toolbar and generate axial curves very rapidly. The dependence on context increases efficiency of the user because the symbolic elements available to the user at any time are only those which he would in fact logically need in the current situation.
In another embodiment of the present invention, points and/or ranges of a qualitatively predeterminable synchronicity can be entered for pathxe2x80x94path relationships. Thus, the user has an opportunity to define points for the beginning of increasing or decreasing synchronization within the diagram for the pathxe2x80x94path relationships of the leading axis and the following axis with the help of an input device. The synchronization ranges (from the beginning to the end of the increasing or decreasing synchronization) are calculated by the system on the basis of the defined relationships and are plotted graphically in the corresponding section of the abscissa where the movement of the leading axis is described. Through this graphic capability, a user can get a very good idea of the synchronicity of the axes involved in a movement sequence, and can introduce further optimization on the basis of such information.
In another embodiment of the present invention, any desired relationships of up to three parameters inherent in the system, instead of or in addition to path-time curves and/or path-time relationships, can be vizualized in a blank diagram. In addition to such quantities as path and time typically used in these types of diagrams, it is also possible, for example, to vizualize pressure variations in an installation over time.
In another embodiment of the present invention, there may be automatic monitoring and/or vizualize of violations of limits in the path-time curves and/or the path-time relationships. Such monitoring and verification function inherent within the system removes a burden from users as they need not perform these functions themselves, but instead can concentrate on their actual engineering activities.
Advantages of the present invention thus consist in particular of the ability for a user to formulate movement relationships of axes in graphic working diagrams. This feature makes it possible to introduce a stronger mechanical engineering-oriented viewpoint into the programming of machine tools. Machine designers and mechanical engineers who think very much in terms of path-time diagrams or pathxe2x80x94path relationship diagrams can thus create programs for process control, and, in particular, for movement control in an efficient manner. In particular, the efficiency of this type of programming is increased by the fact that the programs for the controllers are automatically generated from the diagram inputs. In addition, these diagrams are also highly suitable for guaranteeing uniform and unambiguous communication between the mechanical engineer and the electrical engineer.